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敦煌核桃生产发展缓慢,其主要原因是越冬伤亡问题。虽说有一些树令高达一百五十年左右的、顶花芽结果的圆核桃老树,但其结果母枝还是年年越不了冬,且产量很低。园艺场有一株占地零点二亩的老核桃树,每年只结二百至三百个果。引进的树种也因幼树越冬困难;成活率很低,个别在立地条件较好处生长的小树,进入结果期很晚,最早要十二年左右,并且也很不丰产。所以全县只保留下来九十七株核桃树。由此可见,我县发展核桃的关键在于
Dunhuang walnut production is developing slowly, the main reason is the winter injury. Although there are some trees up to 150 years old, the top flower buds of the old walnut trees, but the result of the mother or less winter, and the yield is very low. Horticultural field has an area of 1.2 acres of the old walnut trees, each year only two hundred to three hundred fruit. The introduction of tree species also because of the young trees overwintering difficult; survival rate is very low, individual site conditions better growth of small trees, into the fruition of the late, at least as early as 12 years, and is not very productive. So the county only retained 97 strains of walnut trees. This shows that the development of walnut in my county lies